Knee Injections

The practice of surgery has advanced greatly in recent years, and the diagnosis and treatment of conditions has become very technically advanced. Surgical techniques are being refined and improved upon all the time, with keyhole surgery and short stays in hospital now being the norm for many procedures.

However, regardless of the advances in the field of surgery and in the areas of infection control and risk management, although the general risks of undergoing surgery can be minimised there is still no such thing as entirely risk free surgery.

Prior to undergoing any kind of surgical procedure your surgeon will first focus with great care on taking a detailed history, performing a thorough clinical examination and potentially supplementing this with special investigations, such as X-rays, ultrasound scans or MRI scans, in order to reach a clear diagnosis. The definitive treatment of many conditions will inevitably involve a surgical solution, for example joint replacement for severely arthritic joints. However, for most conditions, surgery is kept as a last resort, and only undertaken when the potential benefits are felt to outweigh the potential risks, and when all other appropriate non-surgical (referred to as ‘conservative’) treatments have already been tried.

Steroids (also called cortisone) are very powerful anti-inflammatories, and so can be very useful for treating conditions where there is inflammation. The steroid is normally mixed with a bit of local anaesthetic. The local anaesthetic works very quickly and gives rapid pain relief but also wears off quickly, after several hours. Steroid, however, can take 24 or even 48 hours to kick in and start working. For the first couple of days after a steroid injection the area may be uncomfortable, with a burning feeling, but this nearly always then disappears.

People are sometimes concerned about the possible side effects of a steroid injection, associating it with the concept of being ‘on steroids’. The significant potential side effects that are sometimes associated with steroid, such as water retention, thinning of the bones, problems with hormones and so on actually relate to patients being given very high doses of steroids or being put on long courses of steroid tablets, and this does NOT apply to being given a local steroid/cortisone injection, which is something that is given very frequently in association with sports injuries or repetitive strain injuries.

The conditions that may respond very well to steroid injections are:-

knee arthritis

hip arthritis

shoulder subacromial impingement

shoulder supraspinatus tendonitis

shoulder acromioclavicular joint arthritis

some forms of tendonitis (especially if the tendon sheath is inflamed)

Hylans are molecules that are found within the normal fluid within a joint. They are very long chain molecules, so when provided in a liquid form they are very viscous. There are some people who think that by injecting hyaluronic acid into a knee you are ‘lubricating’ the joint – like changing the oil. There are others who believe that injecting hylans into a joint has a chemical/drug effect. Whatever the actual underlying processes might be, it has been shown that injecting hyaluronic acid into an arthritic joint gives significant symptomatic improvement in over 75% of patients, with decreased pain and increased mobility. Some patients feel symptom improvement straight away after an injection, but in many it can take a few weeks before the full benefit is felt. The degree and length of symptom improvement does vary considerably between patients, but some people gain significant benefit for up to 12 months after an injection.

Some insurance companies will fund hyaluronic acid injections but others won’t, and the injection can cost a fair amount of money. So, if you are covered my medical insurance then it is important that you do check with your insurer that your particular policy does cover this, otherwise you will end up having to cover the hospital bill for the injection yourself.